Focusing electric arc lamp



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POGUSING ELECTRIC ARG LAMP. No. 302,961. Patented Aug. 5, 1884.v

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No. 302,961. f Patented A11. 5 1884.

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Nv PETERS. Pnomu c.

UNITED STATEs PATENT OEETEE.

ELIHU THOMSON, OF NEW BRITAIN, CONNECTICUT, ASSIG-NOR TO THETHOMSON-HOUSTON'ELECTRIC COMPANY, OF CONNECTICUT.

FOCUSING E-LECTRlC-ARC LAMP.

EPBCIFICATION forming part of Letters Patent No. 302,963., dated August5, 1884.

Application filed October 8, 1883. (No model.)

To all whom t may concern:

Be it vknown that l, ELIHU THOMSON, a citizen of the United States, anda resident of New Britain, in the county of I-Iartford and relativerates tolaeep the arc always at the same point.

My invention is designed more especially to provide a simple andeffective means, in small compass, whereby the desired focusing movementmay be imparted to the carbons; t provide a means whereby thecarbon-carriers of such lamps may be suitably guided and prevented frombinding when the lamp is subjected to jarring; to so construct thecarbon carriers or supports of a focusing-lamp that they may be adjustedin any desired direction lfor the purpose of bringing the carbons intoline or for insuring the formation of the are at the desired point; inafocusing-lamp whose carriers are mechanically connected so as to movetogether in feeding to secure, as far as possible,a movement of theupper carbon only when the carbons are to be separated to form the arc,to thereby increase the sensitiveness of the mechanism in case ofoverfeed of the carbons', and to lsecure the shortest possible lampcapable of giving the proper action.

My invention consists, principally, in making one of the carrierscompound, or in two parts capable of slight movement upon one another.One of said parts is mechanically connected with the othercarbon-carrier, so that the two, whenever they move, will move togetherat the proper relative rates. The other part is under the control of themechanism by which the separation of the carbon is eifected and the feedcontrolled. The latter part carries the carbon, and when it is actuatedto form the are is permitted to move without imparting movement to theother portion and the mechanically-connected opposite carbon.. Vhen thecarbons are so far consumed as to necessitate a feed, the two portionsof the compound carrier are engaged with one another,and the feedmovement permitted in that portion which carries the carbon will beimparted through the other portion to the opposite carbon.

My invention consists, also, in certain details of construction ofparts, hereinafter described and claimed, whereby the general objects ofthe invention are eifected.

In the accompanying drawings I have shown only the parts directlyconcerned in effecting the results, the magnet system and the circuitsand connections being omitted, as any of the well-known arrangements aresuitable, and they are not especially related to the mechanicalconstructions forming the subject of this patent.

In the drawings, Figure l is a front elevation of the mechanicalportions of a lamp embodying my invention. Fig. 2 is a plan of the sameon a cross-section line x a: of Fig. 1. Fig. 3 is a side elevation ofthelamp. Fig. 4 is a top view of the lamp. Fig. 5 is aside View, partly insection, oi' the compound carrier and the carbon-separating and feed-controlling device, here shown as a clutch or clamp, of a constructionembodied in some of my prior patents. Fig. 6 is cross-section of the armD, Fig. 2, on the line y y.

In Fig. l, C is the case containing the mech anism ofthe lamp. Itsupports the bushings or guides b b2, through which the upper and lowercarbon-carriers,It R2, respectively,slide,

l those of the latter being insulated, as shown in black, from the caseC C. The carriers E E2 forni or are provided with rack-rods, and gearwith the wheels G H,respectively, which latter are also insulated fromeach other by means of a suitable bushing or bushings, topreventelectrical connection between the carriers It R2. The wheels G II areupon a shaft, c, mounted in standards d d. (See Fig. 3.)

E E2 are the carbon-holders, respectively, supported from arms orbrackets F D,attached to the carriers. The ratio of the gears is such asto give a rate of motion to the carrier E in descending'o'f about twicethat of R2 in siinultaneously ascending, although this proportion issubject to change, according to relative softness and size ol' carbonsused. A ver- IOO tical guide-rod extending through the casing orattached to it is shown at T. Arms or guide-pieces V \V, attached,respectively, to the arms F D and bearing on said rod, serve to steadythe carriers and prevent them from binding in their bushings b if. Thelower holder, Ff, has an independent upward and downward adj ustment insleeve or bushing B on the end of arm D, and may be set therein at anydesired height by the set-screw c or other suit-able means. By thisadjustment the earbons may be set so as to be in contact at the focus ofthe reilector Y. The bushing B is itselfI carried by a plate or arm, j",(see Figs. 3 and 6,) which is capable of horizontal adjustmentlimgitudinally or laterally upon the arm l), and may be clamped orsecured to said arm in any desired position by means ot' a clamp, y, orother device. The lower carboirliolder, F2, is thus given a verticaladjustment and a horizontal. adjustment in all directions. The uppercarbon holder, E, borne in like manner by the arm F, may or may not havesimilar adjustments.

The carbonseparating and feed-controlling device or mechanism may beoli' any desired kind. l. prei'er, however, to employ a clutch of anysuitable characterwsuch, for instance, as that shown-consisti ug ofthebody K,partly encircling the carrier lt, Figs. l, 2, and 5, and havingahinged cam-lcver or toe, t, adapted to bear on the carrier,a `linedreleasingstop, l?, therelor,and a clamping or clutching spring, S,acting to fasten the cam or toe upon the carrier when the cam-lever I1is lifted out of engagement with the stop l?. This construetion oli'clutch is described and shown in other prior patents granted tome. Theclutch is lifted and lowered vertically bythe agency ot' any known andsuitable magnet system, (not shown and not l'orming any part of my presentinventioln) the only requisite being that it shall lil't the carbonsapart by raising the clutch when the arc is too short, and lower theclutch to the stop F, or beyond, when the are is too long, and perl'ormthis action in a gradual manner without quick pulsation or jerks. Thecarrier 1, with which said clutch, clamp, or other lil'ting andl`eed-controlling mechanism engages, is the compound carrier, and is notconnected with the other carrier by a rigid or constant mechanicalconnection, but is so made as to be capable ol" moving a slight distanceupward without necessarily imparting movement through the intermediate1neehanism to the other carrier, RL. This may be accomplishcd bytheconstruction shown in Figs. il. and 5, where M indicates the rack forthe carrier R. This rack is not xedly attached io the carrier, but isi'rcely movable in or upon the carrier between stops s s, as indicated,so that the carrier lt itself may have a slight in dependent verticalplay, determined bythe distance between the stops s s, and maytherel'ore be lil'ted, by the action of the clutch or other device. whenthe are tobe formei'l, without imparting movement to the rack M and thelower carrier and carbon. The rack M is made of' sufficient weight tobalance the rackr0d and carrier t2, Fig. l., :tud its accompanyingparts, so that no tendency to movev ment exists unless the carrier Randits paris add their weight to that of the rack M, when the clutch K isreleased. The parts thus con stituted act as follows: In Fig. 3 thecar-bons are shown in place in the rellector Y, ready for use. "When theclutch is lii'ted by the assumed magnet system, the slight play ol" thecarrier R outside the rack M allows l'ornnition ofthe are without anymovement ol" the gearing, which remains at rest. The lowering ot theclutch to l'eed the cai-bons adds the weight of R, F, and l5, &c., tothat oli' M, causing leedv ing of both earbons at their proper .rates bythe rotation oi' the gear-wheels or other intermediate mechanism.Should, however, an overl'eeding take place and the carbons run too neartogether, as may sometimes happen, there is at once a renewed lii't bythe clutch, as at first, without disturbing or requiring thel gearing totake part therein.

Itis to be understood that the mechanism described is adapted to usewith dillerential magnet systems or shuntfleeding magnet systems to workupon a circuit with other lamps, or with a current strength ot' uniformamount; or it may be used with varying currents to work alone witheither a dill'erential or other magnet system, with or withoutderived-cir cuit magnets. It is to be understood, also, that in thepractice ol" my invention the disconnection ol" the i'novements oi' thetwo rods lt R during lii't of the carbon is claimed, broadly, whetherellected by the agency ol' gearing connections or their mechanicalequivalents.

The position ol" the are during burning and the relation of the partsrender possible a very compact lamp, such as is readily adapted to usewith the ordinary stamlard locomotive i head-light box and reflector,the case (i, con-` taining the Ineclianisimbeiiig supported so as tooccupy a position immediately back oi the reflector.

iVhat I claim as my invention is 1. In an electric-arclamp whosecarriers arc mechanically connected so that the i'eed movement of oneimparts or is accompanied by a corresponding feed movement ol the other,a

tif.:

compound carrier made in two parts, 011e ot Y which supports the carbonand is capable ola slight independent movement upon the other, while thelatter is mechanically connected with the other carbon-carrier, so as toimpart movement to it, as and `for the purpose described.

2. In a focusing electrical-c lamp havingsuitable connecting mechanismto impart a proper relative feed to the two carbons, the fnnnbina tioncfa carbon-carrier having a separate or i ndepcndent lifting moxv'ementindepem'ient oi' the aforesaid connecting mechanism, andcarbon-adjusting mechanism engaging with said carrier.

3. The combination, substantiallyas described, of a carbon-carrierconstructed in two parts, one of which supports the carbon,while theother is movable between two stops upon the first part, acarbon-separating and feedcontrolling device engaging with the firstpart, and intermediate connecting mechanism between the second part andthe carrier for the opposite carbon, as and for the purpose described.

4. The combination, substantially as described, of the carrier, thecarbon liftingvand feeding clutch engaging therewith, the rack M,supported upon and movable between stops on said carrier, andintermediate toothed wheels between said rack and the rack for the othercarrier, as and for the purpose described.

5. The combination of the rack M, thelower carrier and its parts, andthe intermediate wheels, balanced as described, and theindependently-movable carrier arranged to add its weight to the rack,and thus cause a feed when released by the feed-controllin g devices, asand for the purpose set forth. v

G. The combination, in a focusing electric lamp, of a case containingthe mechanism back of the are, carbon-feeding rods projecting therefromupward and downward, respectively,and arms extending at right anglestherefrom, bearing the carbon-holding clamps, the upper carbon beingborne by the part attached to the upper end of the upper feed-rod, andthe other or lower carbon being borne by the part attached to the lowerfeeding-rod, substantially as set forth. L

7. rlhe combination, in an electric lamp, of a feed-rod, R or It?,engaging with the feedeontrolling mechanism, an arm or bracket eX-tending transversely from the same, and carrying at or near itsextremity a carbon clamp or holder, and a guide bar or rod, T, againstwhich the arm or bracket bears, as and for the purpose described.

8. The combination, in an electric lamp, of the feed rods or carriers RIt, gearing with a common feed-controlling mechanism,the arms orbrackets F and D, the guide-rod T, with which the arms engage, and thepositive and negative carbon-holders E E, supported, respectively, fromthe arms F and D.

Signed at Boston, in the county of Suffolk and State of Massachusetts,this 5th day oi' October, A. D. 1883.

ELIHU THOMSON.

Witnesses:

Josnri-I J. SKINNER, JAMns F. MEENGH.

